LM2937-3.3

LM2937-2.5, LM2937-3.3 400mA and 500mA Voltage Regulators February 1998 LM2937-2.5, LM2937-3.3 400mA and 500mA Voltage Regulators General Description The LM2937-2.5 and LM2937-3.3 are positive voltage regulators capable of supplying up to 500 mA of load current. Both regulators are ideal for converting a common 5V logic supply, or higher input supply voltage, to the lower 2.5V and 3.3V supplies to power VLSI ASIC’s and microcontrollers. Special circuitry has been incorporated to minimize the quiescent current to typically only 10 mA with a full 500 mA load current when the input to output voltage differential is greater than 5V. The LM2937 requires an output bypass capacitor for stability. As with most regulators utilizing a PNP pass transistor, the ESR of this capacitor remains a critical design parameter, but the LM2937-2.5 and LM2937-3.3 include special compensation circuitry that relaxes ESR requirements. The LM2937 is stable for all ESR ratings less than 5Ω. This allows the use of low ESR chip capacitors. The regulators are also suited for automotive applications, with built in protection from reverse battery connections, two-battery jumps and up to +60V/−50V load dump transients. Familiar regulator features such as short circuit and thermal shutdown protection are also built in. Features n Fully specified for operation over −40˚C to +125˚C n Output current in excess of 500 mA (400mA for SOT-223 package) n Output trimmed for 5% tolerance under all operating conditions...